pikuri-thunderbird lets a pikuri agent search and read the user's *local* Thunderbird data — mail folders and cached calendars — by reading Thunderbird's own on-disk profile. It never speaks IMAP/POP3/SMTP itself and never egresses: search and read are both inbound-only, so the v1 demo (+bin/pikuri-thunderbird+) breaks the lethal trifecta by construction, exactly like +bin/pikuri-corpus+. Mail search rides Thunderbird's Gloda index (+global-messages-db.sqlite+) as a pre-decoded corpus: pikuri copies a consistent snapshot, builds its own ephemeral FTS5 index over the decoded columns, and serves ranked search + full-body reads with no MIME parsing. Calendar reads come from the +calendar-data/*.sqlite+ stores (normalized columns, no ICS parser for the common case). Any *outbound* action (compose a mail, create an event) is a v2 feature and is always a human-gated hand-off to Thunderbird's own UI — pikuri writes nothing to Thunderbird's stores and sends nothing itself. See +pikuri-thunderbird/DESIGN.md+ and +ideas/thunderbird.md+.